Wall-anchor



N. K. BOWMAN.

WALL ANCHOR.

APPLICATION FILED 0512.3, my.

Patented NOV. 8, 1921.

PATENT OFFICE.

NEWTON K. BOWMAN, OF NORTH LAWRENCE, OHIO.

WALL-ANCHOR.

Specification of Letters '.Patent.

Patented Nov. 8, 1921.

Application led December 3, 1919. Serial No. 342,103.

To all lwhom t may concern Be it known that I, NEWTON K. BOWMAN, a citizen of the United States, residing at No1-th Lawrence, in the county of Stark and State of Ohio, have invented certain new and useful Improvements in 'Wall-Anchors, ot which the following is a specification.

rThis invention relates to an improved anchoring device, being particularly designed for use as a short wall anchor for anchoring a mining machine to the breastof a mine tunnel, and has as one of its principal objects to provide .an anchor which may be inserted in a hole 1n the mine tunnel breast and then easily and quickly operated to coact with the wall of the hole for securing the anchor therein.

The invention has as a further pbject to provide an anchor employing gripping dogs, wherein said dogs will be mounted directly upon the anchor body or shank and wherein said shank will be formed to provide an expanding element for spreading the dogs.

A further object of the invention in this connection is to provide an anchor wherein as the pulling stress upon the anchor body is increased, the gripping dogs will be spread apart with correspondingly increased force for holding the anchor against displacement.

And the invention has as a still further object to provide an operating member for the dogs and wherein said member will also form a clamp acting to hold the dogs upon the anchor body.

Other and incidental objects will appear hereinafter.

In the drawings:

Figure 1 is a side elevation showing my improved anchor inserted in a hole in a mine tunnel breast, this view illustrating the initial position of the parts,

Fig. 2 is a similar view showing the gripping dogs of Vthe device expanded,

Fig. 3 is a longitudinal sectional view more particularly illustrating the mounting of the dogs, and

Fig. et is a perspective view showing the device in detail.

In carrying the invention into effect, I employ a preferably cylindrical anchor body 10 provided at its outer end with a hook 11 and formed in the inner end portion of the body at opposite sides thereof are grooves 12. As particularly shown in Fig. 3, these grooves incline laterally and outwardly toward the inner end of the body and define an intervening expanding element 13 at the inner end portion of the body. Leading from the inner ends of the grooves along opposite sides of the body to the outer end thereof are channels 14.

Mounted to slide within the grooves 12 are gripping dogs 15 substantially wedge shaped in cross section and each provided with a plurality of teeth 16, the dogs seating at their inner edges against the bottom walls of the grooves. Connecting these dogs is a sub' stantially U-shaped operating member 17 therefor. This operating member is prefer-y ably Jformed from a length of suitable resilient material bent into proper shape and is arranged to embrace the anchor body, the arms of said member being freely received within the channels 14. The gripping dogs are threaded upon the inner ends of said arms and these arms act to resiliently clamp the dogs within the grooves 12. Consequently, the operating member will serve to retain the dogs in position within the grooves 12 while, as will be at once appreciated, said member may be manipulated for sliding the dogs longitudinally within said grooves. In this connection it will be observed that the channels 14 are inclined downwardly toward the outer end of the anchor body so that the outer end portion of the operating member will not extend across the bight of the hook 11 so as to interfere with the engagement of a cable with said hook. Further. it is to be noted that when the dogs are 'shifted along the expanding element 13 away from the hook 11, the bend of the operating member 17, at the outer end of said member, will engage the hook 11 and 'will thus co'act with the body for limiting the dogs in their movement. Accidental displacement of the dogs from within the grooves 12 will thus be prevented so that when the device is being handled or carried about from place to place, the dogs cannot be thrust forwardly out of engagement with the body.

In the practical use of the device a hole, as indicated at 18, is first drilled into the breast of a mine tunnel, this hole being preferably about two inches in diameter and twelve inches deep. The operating member 17 is then drawn outwardly upon the anchor body to retract the gripping dogs within the deeperV portions of the grooves when the iio anchor body is inserted into the hole. The operating member is then shifted inwardly for spreading the gripping dogs outwardly into engagement with the wall ofthe hole the expanding element 13 to coact with the gripping dogs for wedging the dogs apart into binding engagement with the wall of the hole so that the anchor body will then be securely locked in position. Accordingly, as suggested in dotted lines in Figs. 1 andk 2, a cable may be connected with the hook 11 for supporting a mining machine to operate against the mine tunnel breast. In this connection it will be noted that pull of the cable upon the anchor body will tend to expand the dogs to more firmly lock the anchor against displacement. As the pull upon the cable is increased, the gripping dogs will be spread apart with correspondingly increased force.A To displace the anchor it is simply necessary to strike the outer end of the anchor body and force the body inwardly within the hole. Inward movement of the anchor body will, of course, free the gripping dogs sufficiently to be drawn forwardly within the grooves 12 by the'operating member 17. Consequently, by then pulling outwardly upon said member, the dogs may be retracted when the anchor may b'e pulled from the mine tunnel breast. It will accordingly be seen that I provide a particulai-ly effective type of anchor and While I have illustrated the device as a short wall anchor for use in mine tunnels and have so described the device still, the anchor may, of course, be employed wherever found applicable or its use would prove desirable,

Without departing from the spirit of the invention.

Having thus described the invention, what is claimed as new is:

1. A wall anchor including an anchor body provided with an expanding element, gripping dogs mounted to coact with said element, and an operating member for the dogs connecting the dogs andextending outwardly along the anchor body.

2. A wall anchor including an anchor body provided with an expanding element, gripping dogs, and means connecting the dogs and yieldably retaining the dogs upon the anchor body to slidably coact with said element.

3. A wall anchor including an anchor body provided with an expanding element, gripping dogs, and a resilient operating member connecting the dogs and yieldably holding the dogs to slidably coact with said element.

4. A wall anchor including an anchor body provided with an expanding element, gripping dogs, and a length of material providing a substantially U-shaped operating member for the dogs embracing the anchor body and supporting the dogs to slidably coact with said element.

5. A wall anchor including an anchor body provided with an expanding element, gripping dogs mounted to coact with said element and shiftable therealong, and means connecting the dogs and disposed to coact with the anchor body for limiting said shifting movement of the dogs.

In testimony whereof I affix my signature.

NEwToN K. BovvMaN. [Le] Witnesses CHAs. L. BowMAN, CLARA GORGAB. 

